The invention relates to a method for teaching a knowledge-based database for automatic defect classification.
In semiconductor manufacturing, wafers or masks are processed sequentially in a number of process steps during the manufacturing process. With increasing integration density, the demands of the quality of the structures formed on the wafers increase. In order to check the quality of the structures formed and to be able to find possible defects, the demand for quality, precision, and reproducibility of the components and process steps used with the wafer is critical. This means that during production of a wafer with a number of process steps, a reliable and early recognition of defects is especially important. In this process, it is necessary to classify the defects that occur in order to thus achieve a fast processing and testing of the wafers.
In earlier versions of “Automatic Defect Classification” (ADC), it was necessary to proceed with a manual classification of the defects on a wafer or on a mask. The teaching of a knowledge base was thus extremely time consuming.